Point-of-use water treatment system

ABSTRACT

The present invention relates to a point-of-use water treatment system unit. The unit includes a filter housing assembly having a filter tank assembly and a closure which utilizes a handle and cammed reciprocating lock blades to secure the closure to the filter tank assembly. A UV tank assembly includes a planar baffle plate and a vaned baffle plate to induce plug flow about a UV lamp assembly. A UV lamp assembly is used which simultaneously electrically and sealingly mounts to a UV tank assembly and electrical cap assembly using a bayonet mount. A bi-planar manifold assembly is used to interconnect components of the WTS unit and to provide an envelope for accommodating a water pipe assembly. The bi-planar manifold assembly enhances the compactness of the design of the WTS unit. Also, a support plate is disclosed which provides support to subcomponents of the WTS unit while also dissipating heat from a UV tank assembly.

TECHNICAL FIELD

[0001] The present invention relates to point-of-use water treatmentsystem (WTS) units for above or below countertop use in homes or officesfor the purposes of removing contaminants from water.

INCORPORATION BY REFERENCE

[0002] This application hereby incorporates by reference U.S. Pat. No.5,536,395 and claims priority to provisional application serial No.60/094,918, filed on Jul. 31, 1998.

BACKGROUND OF THE INVENTION

[0003] The present invention minimizes or overcomes several problemsassociated with previous point-of-use home or office water treatmentsystem (WTS) units. These WTS units are often connected to a faucetusing a faucet diverter valve assembly. Water can be supplied directlyfrom the faucet, or using the faucet diverter valve assembly, can berouted through a WTS unit for removal of contaminants prior to beingdispensed from a faucet. The WTS units often include a carbon blockfilter to remove particulates, an ultraviolet (UV) bulb for destroyingmicroorganisms found in water, and a flow meter to monitor the quantityof water treated over a specified period of time.

[0004] A first problem many WTS units encounter is that filter closurescan be difficult to remove from or install on WTS unit filter housings.This is particularly true of closures that rely upon threadedconnections. The closures combine with the filter housings to formclosed pressure vessels in which filters are stored. The diameters offilters are ideally as large as possible to increase the capacity andlife expectancy of the filters. Similarly, the diameter of filterhousings must be large to accommodate the filters. Conventional threadedconnections between the filter closures and filter housings, which areboth usually made of plastic, often “weld” together. This phenomenon isknown as galling. The “welding” action is partially attributable to thelong period of time between filter changes and also to the wet and warmenvironment in which WTS units operate.

[0005] WTS units often include a UV (ultraviolet) bulb for destroyingmicroorganisms in the water to be treated. These UV bulbs typicallyoperate continuously. After water has not been run through a WTS unitfor a significant period of time, such as overnight, heat from the UVbulb and other electrical circuitry can cause heat to build up insideand elevate the temperature of water stored within the WTS unit. Theresulting increased temperature contributes to plastic creep and the“welding” together of the threads on the filter closure and filterhousing. Because of the large area of contact between the threads,considerable force may be required to break the “weld” on the threadsand release the closure from the filter housing.

[0006] Alternatively, some WTS units use bayonet mounted filterclosures. A problem with this type of mount is that a filter closuremust be accurately aligned with a housing to effect mounting of thefilter closure to the filter housing. Also, even with a bayonet mount,there is still significant joint contact area between the filter closureand the filter housing. Again, significant force may be required tobreak the filter closure free from the filter housing after a longperiod of attachment.

[0007] A second problem associated with WTS units having UV bulbs is thebuild up of heat within the WTS units. Adverse consequences related toelevated temperature include structural degradation of plasticcomponents over time due to creep, discoloration of plastic components,and decreased reliability of electrical circuitry. Also, the temperatureof water stored overnight within a WTS unit can become uncomfortablywarm to the touch when discharged from the WTS unit. Therefore, it isbeneficial for a WTS unit to be designed to minimize its internal heatbuildup.

[0008] Further, most WTS units use plastic molded decorative outerhousings to enclose internal components. These plastic outer housingsdecrease in strength as temperature increases. If the WTS unit is to bewall mounted and must rely solely upon the strength of the outerhousing, then the outer housing must be relatively thick, made of highstrength plastic and resistant to creep induced by high temperatures andmechanical loads. Accordingly, expensive specialty plastics may berequired in making such outer housings.

[0009] A third problem associated with WTS units having UV bulbs is thatUV bulbs are cumbersome to change. The UV bulbs have a limited lifetimeand must be periodically changed. While the UV light emitted by thebulbs is beneficial in destroying chemical bonds in microorganisms,hence severely inhibiting their ability to replicate or reproduce, theUV light can also be harmful to human eyes. Consequently, the UV bulbsmust be mounted without UV light exposure to the installer. Often thisrequires numerous steps such as connecting a UV bulb to a power source,closing a housing about the UV bulb to prevent UV light exposure, andthen energizing the UV bulb to insure that the UV bulb will properlyoperate. Ideally, a UV bulb could be easily and quickly installed withthe UV bulb immediately lighting upon installation to show that it isoperating properly while preventing direct exposure of the UV light tothe operator.

[0010] A fourth problem common to WTS units having UV light disinfectionis that water flowing through a UV tank assembly may not be uniformlytreated or exposed to UV light. A UV bulb is typically mounted in a UVtank assembly with water passing around the UV bulb. All portions of thewater should receive a predetermined minimal exposure or dosage of UVlight. Depending on how the water is directed through the UV tankassembly, portions of the water flow receive lesser or greater amountsof exposure. That is, portions of water that pass most quickly throughthe UV tank assembly tend to receive less UV light exposure thanportions of water that take a slower path and have a longer residencetime. Ideally, all the water would receive the same predeterminedminimum dosage of UV light to ensure a desired kill or destruction ratewithout unnecessarily overexposing certain portions of the water flow.Without steady or plug flow through the UV tank assembly, this objectivecannot be optimally met. Plug flow refers to a “plug” or mass of watermoving together through the system. Plug flow avoids uneven flow rate ofwater through the system.

[0011] Some WTS units utilize water transporting Teflon coilssurrounding a UV bulb to achieve a generally uniform flow rate for allwater. However, the Teflon coils can deteriorate and/or cloud over.Also, the Teflon coils can be damaged by heat. Further, water bornecontaminants may reduce the transmissibility of light through the Tefloncoils over time. Therefore, the coils must be cleaned or replaced incertain water conditions.

[0012] One example of a UV tank assembly that addresses this problem isshown in U.S. Pat. No. 5,536,395. A tank includes a generallycylindrical main portion and a reduced diameter neck portion. Thecylindrical portion has attached thereto an inlet and a coaxiallyaligned annular baffle plate with circular openings therein. Waterenters the inlet inducing circumferential water flow and then passesthrough the openings in the baffle plate. As a result, water flowingdownstream from the annular baffle plate travels in a generally spiralmotion about a UV bulb disposed within the UV tank assembly. The waterthen passes to the reduced neck portion before exiting the tank throughan outlet fitting. While this UV tank assembly design providessatisfactory flow characteristics, the tank is expensive and difficultto manufacture due to numerous deep drawing operations required to formthe tank. Further, there are numerous machining operations which must beperformed on stainless steel components which also increases thecomplexity and cost of manufacture.

[0013] Another drawback conventional WTS units have is the use of aplurality of tubes to fluidly interconnect the various components of theWTS units. Individual tubes are typically used to interconnect inlets,outlets, UV subassemblies and filter subassemblies and flow monitoringdevices. The large number of tubes used makes assembly inconvenient andtime consuming. Further, tubes can become brittle over time and mayeventually have to be replaced. With this complexity of tubes and tubeclamps, replacement of parts is difficult for the average consumer.Also, as the tubes are non-structural members, additional supportingmembers must be used to support components such as flow meters and UVand filter subassemblies apart from support provided by decorativehousings of the WTS units. Moreover, designs utilizing tubes makesoptimization of the compactness of a WTS unit difficult.

[0014] The present invention includes designs and features whichovercome, or at least minimize, many of the problems identified abovewhich are encountered by previous water treatment system units.

SUMMARY OF THE INVENTION

[0015] The present invention includes a WTS unit which has a uniquefilter closure and attachment mechanism that allows the closure to beeasily and quickly secured to and removed from a filter housing. Thefilter housing has a filter chamber for receiving a filter. The closurereleasably seals with the housing assembly to form a closed pressurevessel. The attachment mechanism is ideally attached to the closure andutilizes a mechanical advantage, preferably in the form of a pivotinghandle which cams a pair of reciprocating lock blades into and out ofengagement with one or more blade receiving openings on the filterhousing.

[0016] The present invention also covers a WTS unit having a UV tankassembly, a UV bulb assembly received within the UV tank, and a heatdissipating support plate juxtaposed the UV tank assembly. Thisarrangement allows heat generated by the UV bulb assembly andtransferred to the UV tank to be readily transferable to the supportplate and then the atmosphere. Use of the heat dissipating support platealso allows low strength decorative outer housing components to be usedwith the WTS unit as the support plate provide structural support tointernal components and for wall mounting of the WTS unit.

[0017] A point-of-use water treatment system is disclosed having a base,a UV tank assembly, an electrical connector cap assembly and a UV lampassembly. The cap assembly attaches to the UV tank assembly. The UV lampassembly simultaneously mounts to the cap assembly and UV tank assemblyto form a closed pressure vessel and to electrically communicate withthe cap assembly. Ideally, a fluid seal is created between the UV lampassembly and the tank assembly while the UV lamp assembly bayonet mountsto the cap assembly to create electrical communication therebetween.Further, the UV bulb assembly preferably includes a light pipe which isvisible from the exterior of the WITS unit to indicate when the UV lampassembly is operating.

[0018] A UV tank assembly is provided which includes a generallycylindrical sleeve and first and second longitudinally spaced apartannular baffle plates. The first baffle plate is ideally planar and hasa plurality of openings therein. The second baffle plate is preferablyvaned. When a UV lamp assembly is placed within the UV tank assembly,water flowing from the first baffle plate to the second baffle platetravels in a spiral path about a UV bulb providing the water generallyuniform exposure to UV light. This particular UV tank assembly isrelatively simple in construction and inexpensive to manufacture.

[0019] The invention further includes a WITS unit having a UV subsystem,a filter subsystem, a flow monitor, a base and a bi-planar manifold. Themanifold has first and second halves which are joined together tocooperatively provide conduits which fluidly interconnect the filtersubsystem, the UV subsystem and the flow monitor. The filter subsystemrests upon a first plane of the manifold and the UV subsystem rests upona second elevated plane of the manifold with the flow monitor beingpositioned in an envelope created beneath the second plane of themanifold and the base of the WTS unit. This arrangement allows for acompact design for the WTS unit.

[0020] It is an object of the present invention to provide a WTS unitwhich has a filter closure which is easily installed on and removed froma filter housing even after the filter closure has been mounted to thefilter housing for an extended period of time.

[0021] Another object is to provide a filter closure having anattachment mechanism which utilizes a mechanical advantage such thatundue force or strength is not required by a user to effect removal ofthe filter closure.

[0022] An additional object is to provide a high thermal conductivityand high strength support plate to support major components of a WTSunit while enhancing heat dissipation from the WTS unit.

[0023] Yet another object is to provide a WTS unit having a UV lampassembly which allows a UV bulb, in a single quick movement, to beconcurrently electrically connected to a power supply while fluidlysealing with a UV tank assembly thereby eliminating exposure of UV lightto a WTS unit user. This eliminates the extra step of locating andattaching a wiring harness to complete assembly.

[0024] Another object is to provide a UV tank assembly which isinexpensive to manufacture yet cooperates with a UV bulb to allowgenerally uniform flow and UV light exposure to water passing by the UVbulb.

[0025] Still a further object is to provide a WTS unit having abi-planar manifold assembly which interconnects with the majorcomponents of the WTS unit to provide simple yet reliable fluidconnections therebetween. The manifold assembly provides structuralsupport to other subcomponents and partially defines an envelope forplacing a flow meter and monitor assembly.

[0026] Another object is to provide a WTS unit having a UV bulb assemblywith a light pipe thereon, the light pipe being replaceable with the UVbulb assembly and extending through an opening in the outer housing ofthe WTS unit to indicate when a UV bulb is operating.

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] These and other features, objects, and advantages of the presentinvention will become readily apparent from the following description,pending claims, and accompanying sheets of drawings where:

[0028]FIG. 1 is a perspective view of a WTS unit, made in accordancewith the present invention, connected to a faucet using a faucetdiverter valve assembly;

[0029]FIG. 2 is a rear elevational view of the WTS unit;

[0030]FIG. 3 is an exploded perspective view of major subcomponents ofthe WTS unit;

[0031]FIG. 4 is a fragmentary skeletal perspective view of the WTS unit;

[0032]FIG. 5 is an exploded view of a filter housing assembly and filterblock assembly;

[0033] FIGS. 6A-C are fragmentary perspective views showing a filterblock assembly being removed from the WTS unit;

[0034] FIGS. 7A-D are, respectively, an exploded perspective view, arear elevational view, a bottom plan view and a sectional view takenalong line 7D-7D of FIG. 7C of a filter tank assembly;

[0035] FIGS. 8A-D are, respectively, an exploded perspective view, a topplan view, a sectional view taken along line 8C-8C of FIG. 8B and abottom plan view of the filter block assembly;

[0036]FIG. 9 is an enlarged exploded perspective view of a filter capassembly;

[0037] FIGS. 10A-D are, respectively, a top plan view, a bottom planview, a sectional view taken along line 10C-10C of FIG. 10A, and asectional view taken along line 10D-10D of FIG. 10B;

[0038]FIG. 11 is an exploded perspective view of a UV tank assembly anda heat dissipating support plate;

[0039] FIGS. 12A-C are a series of fragmentary perspective views of a UVlamp assembly being installed in a WTS unit;

[0040] FIGS. 13A-E are, respectively, an elevational view, a top planview, a sectional view taken along line 13C-13C of FIG. 13B, a bottomplan view and an enlarged fragmentary view from FIG. 13C of the UV lampassembly;

[0041]FIG. 14 is a fragmentary perspective view of the UV tank assembly;

[0042] FIGS. 15A-D are a top plan view, an elevational view, a rotatedelevational view and a perspective view of a vaned baffle plate utilizedin the UV tank assembly;

[0043] FIGS. 16A-D are an exploded perspective view, a perspective view,a bottom plan view and an inverted sectional view taken along line16D-16D of FIG. 16C of an electrical connector cap assembly;

[0044] FIGS. 17A-D are an exploded perspective view, an elevationalview, a top plan view and a sectional view of a lamp assembly takenalong line 17D-17D of FIG. 17C;

[0045] FIGS. 18A-B are an enlarged fragmentary view taken from FIG. 17Dof the UV lamp assembly and a corresponding view from an alternativeembodiment for a UV lamp assembly;

[0046] FIGS. 19A-F are an exploded perspective view, an elevationalview, a bottom plan view, a left side view, an upper perspective view,including a heat dissipating support plate, and a lower perspectiveview, including the support plate, of a manifold assembly; and

[0047]FIG. 20 is an exploded perspective view of a flow monitor assemblyincluding a water pipe assembly.

BEST MODE(S) FOR CARRYING OUT THE INVENTION

[0048]FIGS. 1 and 2 show a WTS (water treatment system) unit 10 made inaccordance with the present invention. WTS unit 10 uses carbon blockfiltration to filter particles and remove certain chemical contaminantsfrom water. A UV light system is employed to destroy microorganisms. Amonitor is used to report on the status of the filtration and the UVlight systems.

[0049] WTS unit 10 includes a front outer housing 12, a rear outerhousing 14, and a flow monitor assembly 16 which also serves as the basefor the WTS unit 10. Located atop front and rear outer housings 12 and14 are decorative bulb and filter covers 18 and 20. A monitor 22 ismounted in flow monitor assembly 16 which will be further describedbelow. A power supply 24, in the form of a transformer, provideselectrical power to WTS unit 10. A finned aluminum support plate 26extends through an opening in rear outer housing 14 and facilitates thedissipation of heat from within WTS unit 10. A faucet diverter valveassembly 28 routes water to and from WTS unit 10.

[0050] Major subcomponents comprising WTS unit 10 are shown in anexploded perspective view in FIG. 3 and in skeletal perspective view inFIG. 4. These subcomponents include front outer housing 12, rear outerhousing 14, flow monitor assembly 16, support plate 26, a filtersubsystem 30, a UV subsystem 32, a water pipe assembly 34 mounted inflow monitor assembly 16, a manifold assembly 40, a PC board 42 and awall mounting bracket 44. Manifold assembly 40 has an inlet 46 and anoutlet 50 which connect to hoses 52 of faucet diverter valve assembly28. Manifold assembly 40 fluidly interconnects with filter subsystem 30,UV subsystem 32 and water pipe assembly 34. An envelope 54, as best seenin FIG. 4, is formed beneath a portion of manifold 40 and above flowmonitor assembly 16 to accommodate monitor 22 and water pipe assembly34.

[0051] As a quick overview of the water flow path through WTS unit 10,water from faucet diverter valve assembly 28 is introduced into inlet 46of manifold assembly 40. The water then travels from manifold assembly40 to filter subsystem 30 for carbon block filtration. The filteredwater is then discharged from filter subsystem 30 back to manifoldassembly 40. Manifold assembly 40 delivers the filtered water to UVsubsystem 32 for microorganism destruction by exposure to UV light. Thefiltered and disinfected water then leaves UV subsystem 32 and passesthrough water pipe assembly 34. The water finally returns to manifoldassembly 40 and exits manifold outlet 50 and returns back to faucetdiverter valve assembly 28.

[0052] Filter subsystem 30 is shown in exploded perspective view inFIGS. 3, 5 and 6. Components include a filter housing assembly 60, aclosure or filter cap assembly 64 and a filter assembly 66. Filterassembly 66 is retained within filter housing assembly 60. Filter capassembly 64 has a cammed closure and sealingly cooperates with filterhousing assembly 60 to form a closed pressure vessel in which water isfiltered through filter assembly 66.

[0053] FIGS. 6A-C illustrate the removal of filter assembly 66 from WTSunit 10. Decorative filter cover 20 is rotated a quarter turn and isremoved by unthreading from filter cap assembly 64. Next, a handle 152on filter cap assembly 64 is pivoted upwardly causing a pair ofreciprocating lock blades 146, 150 (not shown) to release radiallyinwardly from a circumferentially extending blade receiving groove 98formed in a seal mating mouth 86 of filter housing assembly 60. Filtercap assembly 64 is lifted upwardly breaking a seal between filter capassembly 64, an elastomeric O-ring 144 mounted on filter cap assembly64, and seal mating mouth 86 on filter housing assembly 60. Filterassembly 66 is next lifted from filter housing assembly 60. A new filterassembly 66 can then be placed in filter housing assembly 60. Filter capassembly 64 is pressed down into seal mating mouth 86 of filter housingassembly 60 reestablishing a seal therebetween utilizing O-ring 144.Filter cap assembly 64 is then locked in place by lowering handle 152 toa horizontal position which extends lock blades 146, 150 into bladereceiving groove 98. Filter cover 20 is then reattached atop filter capassembly 64. Handle 152 provides a significant mechanical advantage inreciprocating lock blades 146, 150 into and out of engagement with bladereceiving groove 98, as will be described in greater detail below.

[0054] The individual components of filter subsystem 30 will now bedescribed. Referring to FIGS. 7A-D, filter housing assembly 60 is shown.Filter housing assembly 60 includes a filter housing 70 and a pair ofcooperating split rings 72 a and 72 b. Filter housing 70 has molded onits backside four threaded bosses 74. Supporting ribs 76 and 78 extendbetween and provide support to bosses 74. Filter housing 70 includes alower domed end 80 having inlet and outlet conduits 82 and 84 formedtherein. A pair of threaded bosses 83 are formed on the bottom of domedend 80 to receive fasteners which secure a portion of manifold assembly40 to filter housing 70. Similarly, a pair of threaded bosses 85 areformed on the side of filter housing 70 to receive fasteners used toattach rear outer housing 14. At the top portion of filter housing 70 isinterior seal mating mouth 86 and a retaining flange 90. Seal matingmouth 86 is sized to sealingly engage with O-ring 144 of filter capassembly 64. Split rings 72 a and 72 b have radially inwardly extendinggrooves 92 a and 92 b. Fasteners 96 clamplingy secure split rings 72 aand 72 b about filter housing 70 with grooves 92 a and 92 b capturingretaining flange 90, as best seen in FIG. 7D. Blade receiving groove 98extends the full circumference of filter assembly 66 and is formedbetween flange 90 and corresponding radially interior steps 99 a and 99b formed in split rings 72 a and 72 b.

[0055]FIG. 8A shows an exploded view of filter assembly 66. A carbonfilter block 100 is held between a filter bottom cap 102 and a filtertop cap 104. Block filter 100 is annular and has inner and outer wraps106 and 108, as best seen in FIG. 8C. Filter top cap 104 includes an endplate 110 with a post 112 and oval shaped grip disk 114. Oval shapedgrip disk 114 allows filter assembly 66 to be easily grasped and pulledfrom filter housing assembly 60. Bottom cap 102 has an end plate 116, acentral conduit 118 and two pair of triangular shaped supporting ribs120 and 122 extending therebetween. Ribs 120 have triangular shapedopenings 124 to provide weight reduction. A pair of O-rings 126 areretained in grooves 128 in central conduit 118 of end cap 102. Waterflows radially inwardly from the outside of filter block 100 and exitsthrough central conduit 118 during normal operation of WTS unit 10.Arrows indicate this desired direction of water flow in FIG. 8C. Whenfilter assembly 66 is mounted within filter housing assembly 60, O-rings126 seal between central conduit 118 and outlet conduit 84 (FIG. 7D) offilter housing assembly 60.

[0056]FIG. 9 illustrates filter cap assembly 64 in an explodedperspective view. Elements comprising filter cap assembly 64 includefilter housing cap 142, elastomeric O-ring 144, first and second camlock blades 146 and 150, a handle 152, first and second cam lockretainers 154 and 156, and four fasteners 160. O-ring 144 is held in agroove 145 formed in the outer diameter of filter housing cap 142.Handle 152 and lock blades 146 and 150 are movably captured above filterhousing cap 142 and below lock retainers 154 and 156 when filter capassembly 64 is held together by fasteners 160. Handle 152 is retained torotate between filter housing cap 142 and lock retainers 154 and 156.Handle 152 is attached to lock blades 146 and 150 such that blades 146and 150 radially extend and retract in a horizontal plane as handle 152is rotated downward and upward with respect to filter housing cap 142.When lock blades 146 and 150 are extended, they are adapted to lock intoblade receiving groove 98 of filter housing assembly 60, as has beenpreviously explained in regards to FIG. 6B.

[0057] Lock blades 146 and 150 are generally planar having respectivearcuate engagement portions 162 and 164. Inboard extending pins 166 and170 serve to connect with handle 152.

[0058] Handle 152 includes an arcuate grip portion 172, a pair of spacedapart ears 174 and 176 and an axle 180 connecting ears 174 and 176.Located on the outboard side of ears 174 and 176 are C-shaped cam tracks182, 184 and 186, 190. Pins 166 and 170 of lock blades 146 and 150cooperatively slide in cam tracks 182, 184, 186 and 190 to cause lockblades 146 and 150 to radially extend and retract as handle 152 ispivotally lowered and raised. Referring to FIG. 10C, when handle 152 isin its lowered position and pins 166 and 170 are disposed at the end ofthe tracks, pins 166 and 170 are maximally located from the centers ofears 174 and 176 as are lock blades 146 and 150. When grip portion 172of handle 152 is raised, ears 174 and 176 rotate with pins 166 and 170being cammed toward the center of ears 174 and 176 and adjacent thebight or mid-length portions of cam tracks 182, 184, 186 and 190. Lockblades 146 and 150 correspondingly travel radially inwardly into aretracted position as their pins 166 and 170 move or are cammed radiallyinwardly.

[0059] Referring to FIG. 9, axle 180 of handle 152 is retained to rotatein bearings formed by U-shaped yokes 192 and 194 disposed on the uppersurface of filter housing cap 142 and cooperating U-shaped yokes 196 and200 formed on the underside of cam lock retainers 154 and 156. Diskshaped recesses 202 and 204 are formed in filter housing cap 142 toaccommodate ears 174 and 176. Similarly, slots 206 and 210 are formed incam lock retainers 154 and 156 to facilitate the rotation of gripportion 172. Cam lock retainers 154 and 156 cooperate with the uppersurface of filter housing cap 142 to guide lock blades 146 and 150 inplanar movement between retracted and extended positions. Looking toFIG. 10D, outer and center guide ribs 212 and 214 are located atopfilter housing cap 142 and cooperate with outer and center guide slots216 and 220 formed on the underside of lock blades 146 and 150 to insurelinear motion of lock blades 146 and 150 on filter housing cap 142. Thecamming action of handle 152 with pins 166 and 170 of lock blades 146and 150 allows lock blades 146 and 150 to be easily retracted from bladereceiving groove 98. Again, the problem of interacting threads “welding”together after long periods of non-use in a water treatment system unitis overcome in the present invention by using reciprocating lock blades146 and 150 rather than a threaded connection between filter capassembly 64 and filter housing assembly 60.

[0060] The distance from the center of axle 180 to grip portion 172provides a much larger moment arm than the radial distance from thecenter of axle 180 to contact points where cam tracks 182, 184, 186 and190 bear upon pins 166 and 170. Consequently, a user lifting or loweringhandle 152 enjoys a substantial mechanical advantage in camming lockblades 146 and 150 radially inwardly or outwardly. Also, using diskshaped ears 174 and 176 with C-shaped cam tracks 182, 184, 186 and 190allow pins 166 and 170 to move in a single horizontal plane even thoughcam tracks 182, 184, 186 and 190 move in a circular path as handle 152is rotated. This allows lock blades 146 and 150 to be generally planarand the filter cap assembly 64 to be relatively compact in thickness.

[0061] Referring to FIG. 9, cam lock retainers 154 and 156 haverespective tongues 222 and 224 with holes 226 and 230 therein.Similarly, countersunk holes 232, 234, 236 and 240 are formed in camlock retainers 154 and 156. Corresponding threaded bosses 242, 244, 246and 248 are located atop filter housing cap 142. As suggested in FIG. 9when filter cap assembly 64 is fully assembled, threaded fasteners 160are installed in countersunk holes 232, 234, 236 and 240 and areretained in threaded bosses 242, 244, 246 and 248. Holes 226 and 234 andholes 230 and 232 are coaxially aligned when cam lock retainers 154 and156 are interlocked with one another.

[0062] In operation, filter cap assembly 64 is placed atop filterhousing assembly 60 with handle 152 in an up position and lock blades146 and 150 retracted radially inwardly. This allows lock blades 146 and150 to retract from engagement with blade receiving groove 98 and topass radially within split rings 72 a and b of filter housing assembly60. As filter cap assembly 64 is lowered and pressed into filter housingassembly 60, O-ring 144 slides into sealing engagement with seal matingmouth 86 of filter housing 70. A watertight seal is thus created betweenfilter housing 70, O-ring 144 and filter housing cap 142. Once filtercap assembly 64 is pressed into filter housing assembly 60 with O-ring144 effecting a seal with filter housing 70, filter cap assembly 64 mustbe locked in place. Handle 152 is rotated downwardly to be flush withfilter housing cap 142 with lock blades 146 and 150 being cammedradially outwardly into engagement within blade retaining groove 98.O-ring 144 is compressively and sealingly captured between filterhousing cap 142 and seal mating mouth 86 to maintain a seal betweenfilter cap assembly 64 and filter housing assembly 60 thereby creating aclosed pressure vessel. A generally single motion is thus effective inplacing filter cap assembly 64 in position with filter housing assembly60 and then lowering handle 152 to lock filter cap assembly 64 in place.The reverse is also true. Upon lifting handle 152, lock blades 146 and150 are retracted and filter cap assembly 64 can be easily removed fromseal mating mouth 86.

[0063] PC board 42, as seen in FIG. 3, includes a circuit board 250 uponwhich electronic components and circuitry are mounted. A female plug 252is located near the base of circuit board 250 for receiving power from amale pin (not shown) on a connector cord of power supply 24. At the topof circuit board 250 a connector flange 254 which has a pair of C-shapedcontacts 256 disposed on its front side. Another pair of contacts 260are located near the base of circuit board 250 and are used tocommunicate with monitor 22 regarding the status of a UV lamp—i.e., isthe lamp working.

[0064] UV subsystem 32 is shown in exploded perspective view in FIG. 11along with aluminum extrusion or support plate 26. Components ofsubsystem 32 include a UV lamp assembly 280, an electrical connector capassembly 290, fasteners 292, bulb cover 18 and a UV tank assembly 300.Cap assembly 290 rests atop tank assembly 300 and is secured byfasteners 292 to openings 294 formed in support plate 26. Lamp assembly280 may then be installed in and removed from the combination of capassembly 290 and tank assembly 300. Lamp assembly 280 fits within andelectrically connects with electrical connector cap assembly 290 whilefluidly sealing with tank assembly 300. Bulb cover 18 has a light pipereceiving aperture 282 centrally disposed therein. Threads 296 areformed on the exterior of cap assembly 290 for releasably retaining bulbcover 18. Support plate 26 is adapted to fit about and carry heat awayfrom tank assembly 300 as well as PC board 42 (not shown in FIG. 11).Lamp assembly 280 must be properly installed in and sealed with tankassembly 300 and cap assembly 290, in a bayonet type installation,before cap assembly 290 can provide electrical power to lamp assembly280. Proper installation prevents UV light from escaping from tankassembly 300 and cap assembly 290. Lamp assembly 280 is installed in capassembly 290 and tank assembly 300 with a simple push and quarter turnof UV lamp assembly 280 into a bayonet mount 295 formed in cap assembly290. This installation simultaneous effects a fluid sealing between lampassembly 280 and tank assembly 300 and electrical connection betweenlamp assembly 280 and cap assembly 290, as suggested in FIGS. 12A-C.

[0065] Tank assembly 300 is shown in exploded view in FIG. 11, incombination with lamp assembly 280 in FIGS. 13A-E and individually inFIG. 14. Cap assembly 290 is not shown in FIGS. 13A-E for ease ofviewing. Tank assembly 300 includes a cylindrical stainless steel mainsleeve or tank 302 having inlet and outlet fittings 304 and 306 attachedthereon, an inlet elbow 308, an outlet elbow 310, a bottom closed endplate 312 and a top annular cup-shaped end plate 314. Elbows 308 and 310are affixed to fittings 304 and 306. Pairs of O-rings 316 are used tocreate seals between fittings 304 and 306 and elbows 308 and 310.Mounting clips 315 are placed into slots on elbows 308 and 310 to secureelbows 308 and 310 to manifold 40. A lamp receiving opening 318 isformed in top end plate 314. An annular seal surface 320 on end plate314 is adapted to mate with a corresponding seal on lamp assembly 280 asbest seen in FIG. 13E. End plate 314 also has a horizontal UV lightblock portion 323. A curled end portion 325 helps guide UV lamp assembly280 during insertion and removal relative to tank assembly 300. Also, itreduces the chances of damage from any sharp stamped edges formed on topend plate 314 during manufacture.

[0066] Secured within tank 302 are a lower generally planar baffle plate322 and an upper vaned baffle plate 324. Baffle plate 322 is annular andis welded to the interior of tank 302 using three attachment ears 326,as shown in FIG. 13C, which extend vertically downwardly along the wallof tank 302. Looking to FIG. 14, a diverter plate 330 is welded tobaffle plate 322. Diverter plate 330 is positioned in front of fitting304 to form a wedge shaped entrance chamber 332 and to cause incomingwater to travel circumferentially. Diverter 330 also acts as a UV lightblock for lower elbow 308. A plurality of circular openings 334 arelocated in lower baffle plate 322 to allow water to travel toward upperbaffle plate 324 in a spiral manner, as suggested by the arrows.

[0067] Upper baffle plate 324 is shown in FIGS. 13C, 14 and individuallyin FIGS. 15A-D. Upper baffle plate 324 has a circular hub 336 andtapered vanes 338. Vanes 338 are preferably angled at an angle alpha of13° relative to the plane of circular hub 336. However, angles ofbetween 5° and 45° will also induce acceptable circumferential or plugflow. Gaps 340 are formed between adjacent vanes 338 to allow water toflow therebetween. Three upstanding mounting ears 341 are used to securebaffle plate 324 to tank 302 through a welding operation. As taperedvanes 338 are angled upwardly in the direction of water flow,circumferential flow through gaps 340 is enhanced relative to using aplanar baffle plate like first baffle plate 322 which has only generallyplanar openings 334 therein. Using a vaned baffle plate in the bottom oftank 302 has surprisingly shown less effectiveness in creatingcircumferential or plug water flow in tank assembly 300 relative tousing a planar baffle plate 322 which has circular openings 334 therein.For maximum ease of manufacture and optimal creation of circumferentialor plug flow, the combination of planar baffle plate 322 with circularopenings 334 therein and vaned baffle plate 324 has proven to be veryeffective. This circumferential flow substantially eliminates laminarflow which allows different flow rates of water through the tankassembly 300. The enhanced plug flow of the present invention increasesthe minimal, relative to average, contact time of water exposed to UVlight during operation of WTS unit 10. However, it is also within thescope of this invention that two or more of the vaned baffle platescould also be used to create the spiral or plug flow in a tank assembly.

[0068] Tank assembly 300 is constructed as follows. Tank 302 is cut tolength from stainless steel tube stock. Openings are then stamped insleeve or tank 302 to accommodate inlet fitting 304 and outlet fitting306. Diverter plate 330 is spot welded to baffle plate 322. Baffle plate322 is then plasma welded within tank 302 with diverter plate 330positioned in front of the lower opening which will receive inletfitting 304. Next, upper baffle plate 324 is plasma spot welded to tank302. Inlet and outlet fittings 304 and 306 are swaged into engagementwith the stamped openings in tank 302 and then plasma welded in place.Inlet and outlet elbows 308 and 310 are then attached to inlet andoutlet fittings 304 and 306. Finally, lower end plate 312 and annularupper end plate 314 are plasma welded into place. The tank assembly ispassivated to provide surface conditioning. This method of constructionavoids the use of deep drawn materials, uses shallow drawn end platesand requires no machined parts. Thus tank assembly 300 provides a lowcost but very effective, in terms of plug flow characteristics, UV tankassembly.

[0069] Electrical connector cap assembly 290 serves two generalpurposes. First, cap assembly 290 transfers electrical power from PCboard 42 to UV lamp assembly 280. Second, cap assembly 290 uses abayonet type connection to retain UV lamp assembly 280 mechanically inplace relative to tank assembly 300. Cap assembly 290 rests upon tankassembly 300 and utilizing threaded fasteners 292 is attached to supportplate 26, as suggested in FIG. 11. When UV lamp assembly 280 is properlyheld within cap assembly 290 and tank assembly 300, UV lamp assembly 280is energized and UV light cannot escape from UV subsystem 32. Further,UV lamp assembly 280 also fluidly seals with tank assembly 300, as shownin FIG. 13E.

[0070] Cap assembly 290 is shown in FIGS. 16A-D. Looking to explodedview 16A, components include a plastic molded connector cap 342, apre-mold 344, a lead frame 346 and a pair of clips 350. Lead frame 346has upper and lower pairs of terminals 348 and 349 at its distal ends.Clips 350 each include curved elongate portions 352, intermediate archedcontact portions 354 and end portions 356 and 358. Pre-mold 344 and leadframe 346 are captured within molded connector cap 342 during a moldingoperation which produces cap assembly 290, which is shown in itscompleted assembly in perspective view in FIG. 16B.

[0071] Connector cap 342 has a generally cylindrical main body 366, atunnel portion 368 and an extension portion 370 molded about lead frame346. A bayonet mount 295 is formed atop connection cap 342 to retain UVlamp assembly 280. Bayonet mount 295 comprises inwardly rolled flanges372 and 374. Slots 376 and 378 are formed between rolled flanges 372 and374. The inner edges of rolled flanges 372 and 374 taper downwardly asthey extend away from slots 376 and 378 creating ramped surfaces. Flange372 is shown in FIG. 16D tapering downwardly from slot 378. Formed onthe inside of connector cap 342 are retaining clip walls 380, 382 and384, as best seen in FIG. 16C. Curved elongate portions 352 and endportions 362 and 364 of clips 350 are retained by these clip walls 380,382 and 384, as seen in FIG. 16C. Arched contact portions 354 areexposed on the interior of connector cap 342 and are circumferentiallyspaced from slots 376 and 378. Clip walls 380 and 382 serve as stopswhen lamp assembly 270 is bayonet mounted in cap assembly 290. Afterclips 350 are mounted behind walls 380, 382, and 384, terminals 348 oflead frame 346 are electrically connected to the end portions 358 ofclips 350.

[0072] Terminals 349 are held in a U-shaped mounting pocket 392 formedin extension 370 of connector cap 342, as best seen in FIG. 16C.Interior slots 394 are sized in mounting pocket 392 to hold connectorflange 254 of PC board 42. When mounting pocket 392 is slidably mountedover PC board 42, terminals 349 contacts are held within C-shaped clips256 on PC board 42 (see FIG. 3). Outer flanges 396 are formed onmounting pocket 392 and are sized to be received in the upper portion ofcorresponding slots 574 formed in support plate 26 (see FIG. 19F).Tunnel portion 368 is sized to fit over outlet elbow 310 on tankassembly 300.

[0073] UV lamp assembly 280 is best seen in FIGS. 17A-D and 18A-B. Lampassembly 280 includes a quartz sleeve 402, a bumper O-ring 404, acompression nut subassembly 406 and a bulb/connector subassembly 410. Asbest seen in FIG. 17A, subassembly 410 has a main molded body 412including a pair of radially extending flanges 414, an annular hub 416,and a knob 420. An annular slot 418 is formed in hub 416 and receivesthe upper open end of quartz sleeve 402. At the lower end of hub 416 isformed an annular wedge portion 419 located adjacent compression nutsubassembly 406. A light pipe 422 is held in a press-fit within anopening in knob 420. As shown, light pipe 422 is exposed to a UV bulb424.

[0074] Compression nut subassembly 406 includes a nut 426 with internalthreads 428 which are threadedly mountable to corresponding externalthreads 429 on hub 416. An annular elastomeric overmolded seal member430 encompasses the lower portion of nut 426. In cross-section, sealmember 430 is U-shaped having radially inboard and outboard beads 432and 434. Inner radial seal bead 432 seals with quartz sleeve 402 and hub416. As compression nut assembly 406 is threaded on hub 416, compressionnut 426 bears upon annular wedge portion 419 creating a fluid tight sealtherebetween. Outer radial bead 434 seals (see FIG. 13E) with sealsurface 320 in the mouth of tank assembly 300 when UV lamp assembly 280is bayonet mounted within cap assembly 290. An elastomeric gasket 408,V-shaped in cross section, is interposed between connector body 412 andbulb 424 to retain bulb 424.

[0075]FIG. 18B shows an alternative embodiment for a UV lamp assembly280′ which is similar in design to UV lamp assembly 280 with theexception of compression nut 426. Rather than using elastomeric sealmember 430 having inboard and outboard beads 432 and 434, a seal member430′ is used in conjunction with discrete O-rings 432′ and 434′.L-shaped steps are formed in seal member 430′ to hold O-rings 432′ and434′ in place.

[0076] A pair of electrical terminals 436 is disposed within radiallyextending slots 438 formed in flanges 414. Terminals 436 areelectrically connected to UV bulb 424 by way of filaments 446 and 450.Extending perpendicular to slots 438 are access slots 440 which allowaccess for filaments 446 and 450 to be soldered to respective terminals436. Exposed radial end portions 442 on terminals 436 electricallyconnect with the arched contact portions 354 of clips 350 when UV lampassembly 280 is bayonet mounted within cap assembly 290.

[0077] Referring to FIGS. 12A-C and FIGS. 16 and 18A, UV lamp assembly280 is installed by removing bulb cover 18 and bayonet mounting UV lampassembly 280 in cap assembly 290. Flanges 414, which carry terminals436, are aligned with slots 376 and 378 in cap assembly 290. UV lampassembly 280 is lowered into cap assembly 290 and tank assembly 300.Outer radial bead 434 of compression nut 406 comes into contact withseal surface 320 of tank assembly 300. Knob 420 is rotated 900 withflanges 414 bearing on the underside of rolled flanges 372 and 374 untilstriking retaining clip walls 380 and 384. At this time, arched contactportions 354 of clips 350 of cap assembly 290 are in electricalcommunication with radial end portions 442 on terminals 436 on UV lampassembly 280 thus energizing UV bulb 444. In turn, light pipe 422 is litindicating to a user that UV lamp assembly 280 is properly installed andoperating. Concurrently, UV lamp assembly 280 is locked in place by thebayonet mount 295 while sealing with seal surface 320 of tank assembly300. Bulb cover 18 may then be mounted on the outside of cap assembly290. Light pipe 422 extends through aperture 282 in bulb cover 18.Because light pipe 422 is part of the replacement UV lamp assembly 280,light pipe 422 is thus replaced with every change of UV lamp assembly280. Discoloration of light pipe 422 due to exposure of high energy UVlight is thus of only minor concern in this design of WTS unit 10.

[0078] Manifold assembly 40 is shown in FIGS. 19A-F. Manifold assembly40 is comprised of a bottom manifold half 500 and a top manifold half502 which includes a manifold pipe 504. Bottom and top manifold halves500 and 502 are joined together to form a series of three conduitstherebetween, which along with manifold pipe 504, place the variousmajor subcomponents of WTS unit 10 in fluid communication with oneanother. These conduits include a manifold inlet conduit 506, a manifoldoutlet conduit 510 and a UV subsystem conduit 512. Inlet conduit 506connects between faucet diverter valve assembly 28 and filter subsystem30. UV subsystem conduit 512 connects the outlet of filter subsystem 30with the inlet to UV subsystem 32. Manifold pipe 504 connects the outletof UV subsystem 32 to water pipe assembly 34. Outlet conduit 506 returnswater from water pipe assembly 34 to faucet diverter valve assembly 28.

[0079] Manifold inlet conduit 506 connects an inlet collet assembly 514to a manifold nipple 516. Nipple 516 connects with inlet conduit 82 onfilter assembly 66. As seen in FIG. 3, a duckbill valve assembly 518 isprovided to connect between outlet conduit 84 of filter assembly 66 anda manifold nipple 520 of subsystem conduit 512. Duckbill valve assembly518 prevents the backflow of water from UV lamp assembly 280 to filterassembly 66. UV subsystem conduit 512 extends between nipple 520 andmanifold nipple 522. Nipple 522 attaches to inlet elbow 308 of UV tankassembly 300. A similar nipple 524 is formed on the upper free end ofmanifold pipe 504 which connects to outlet elbow 310. On the undersideof manifold assembly 40 and at the other end of manifold pipe 504 isformed a nipple 528. Nipple 528 secures to an inlet on water pipeassembly 34. The outlet from water pipe assembly 34 is connected to awater pipe outlet nipple 530 on manifold 40. Nipple 530 serves as theinlet to outlet conduit 510. Three threaded bosses 534 are formed on thebottom of manifold assembly 40 to receive fasteners 610 (FIG. 20) whichattach flow monitor assembly 16 to manifold 40.

[0080] Geometrically, manifold assembly 40 generally has a lower planarportion 536, a diagonal riser portion 540 and an upper planar portion542. A UV subsystem circular retaining wall 538 on upper planar portion542 helps center and retain tank assembly 300 when UV tank 302 ismounted atop manifold assembly 40. As filter subsystem 30 is greater inheight than UV subsystem 32, utilizing this bi-planar manifold designallows for the existence of a spatial envelope 54 formed beneath upperplanar portion 542 and above flow monitor assembly 16 in which waterpipe assembly 34 resides. This biplanar manifiold design allows WTS unit10 to be compact in size, which is important on countertops of limitedsize. Also, as manifold assembly 40 is generally integral after beingsonically welded together, no loose hoses are utilized in connectingsubcomponents of WTS unit 10. Thus, an ordinary WTS unit 10 user canrelatively easily replace subcomponents without changing any hoses.Manifold assembly 40 is threadedly secured by two bosses 544 to boss 83on the bottom of filter housing 70 and at two mounting ears 546 tosupport plate 26.

[0081] Referring to FIGS. 19E-F, heat dissipating support plate 26 hasan arcuate portion 560 and a planar portion 562. Arcuate portion 560 isadapted to be juxtaposed with tank assembly 300 (FIG. 4). Radiallyextending fins 564 on support plate 26 provide a large surface area todissipate heat into the atmosphere. Heat generated by UV lamp assembly290 is conducted to sleeve or tank 302 and then to arcuate portion 560.Arcuate portion 560 passes the heat to fins 564 which readily give awayheat to the atmosphere. Arcuate portion 560 and tank assembly 300 arejuxtaposed for approximately 180°. It is envisioned that this area ofcontact could extend from between 45°-270°, depending on the amount ofheat dissipation desired.

[0082] As shown in FIG. 19F, support plate 26 has a pair of apertures568 for receiving threaded fasteners 570 to attach manifold 40. Supportplate 26 also has a pair of openings 572 for receiving fasteners thatalso attach to a pair of threaded bosses 74 located on back of filterhousing 70 (see FIG. 3) and also two vertically spaced correspondingopenings in mounting bracket 44. A PC board-receiving slot 574 is formedin planar portion 562 to retain the vertical edges of PC board 42. Capassembly 290 also is threadedly fastened by fasteners 292 to supportplate 26 at two threaded openings 294 (FIG. 11). Finally, flanges 396 ofcap assembly 290 (FIG. 16) are also retained by slot 574. Consequently,support plate 26 concurrently provides important structural support andheat dissipation capabilities to WTS unit 10.

[0083] Flow monitor assembly 16 is displayed in FIGS. 3, 4, and 20. Asdescribed previously, flow monitor assembly 16 serves as the base forWTS unit 10. Flow monitor assembly 16 includes a bottom housing 602, abottom housing cover 604, a battery door 606, and a battery pack 608,fasteners 610, water pipe assembly 34 and monitor 22. Water pipeassembly 34 and monitor 22 are retained within bottom housing 602. Awater pipe receiving opening 612 and retaining bands 614 are formed inbottom housing 602 to hold water pipe assembly 34. Similarly, foursupport ribs 616 on the top side of bottom housing cover 604 provideunderneath support to monitor 22. Three fasteners 610 pass through threeapertured bosses 620 in bottom housing cover 604 and are used to secureflow monitor assembly 16 to threaded bosses 534 of manifold assembly 40.Similar four other fasteners 610 passes through bosses 621 in bottomhousing cover 604 to attach directly to threaded bosses (not shown) onthe underside of bottom housing 602.

[0084] Water pipe assembly 34 has an inlet 624 and an outlet 626. Waterflowing through water pipe assembly 34 turns a turbine whichelectronically sends water flow information to monitor 22. Inlet 624receives water from manifold pipe nipple 526 and returns the water tonipple 530 of manifold outlet conduit 510 for discharge from WTS unit10.

[0085] Monitor 22 is in electronic communication with UV lamp assembly280, water pipe assembly 34 and battery pack 608. Status informationregarding WTS unit 10 is displayed by monitor 22. An overlay label 618covers monitor 22. Because of the unique bi-planar design of manifoldassembly 40, envelope 54 is created beneath upper planar portion 542 ofmanifold assembly 40. Envelope 54 is best displayed in FIG. 4.

[0086] Front and rear outer housings 12 and 14 form a clam shell housingwhich clamps about the other major subcomponents of WTS unit 10.Referring to FIG. 3, apertured bosses 650 on the left rear side of rearouter housing 14 allows fasteners (not shown) to attach to correspondingbosses 652 in front outer housing 12. Looking to FIG. 2, aperturedbosses 654 allow fasteners to be secured to threaded bosses 85 (FIG. 7B)formed on filter housing 70.

[0087] While in the foregoing specification this invention has beendescribed in relation to certain preferred embodiments thereof, and manydetails have been set forth for the purpose of illustration, it will beapparent to those skilled in the art that the invention is susceptibleto alteration and that certain other details described herein can varyconsiderably without departing from the basic principles of theinvention.

What is claimed: 1- A point-of-use water treatment system comprising: afilter housing assembly having a filter chamber for receiving a filter;a closure which releasably seals with the housing assembly to form aclosed pressure vessel; and an attachment mechanism which utilizes amechanical advantage to releasably secure the closure to the housingassembly. 2- The water treatment system of claim 1 wherein: theattachment mechanism includes a cam and a follower. 3- The watertreatment system of claim 1 wherein: the housing assembly includes atleast one blade receiving opening therein; and the attachment mechanismincludes a handle and at least one blade; wherein the handle can beselectively actuated causing the at least one blade to respectivelyengage and disengage with the at least one blade receiving openingthereby securing and releasing the closure relative to the housingassembly. 4- The water treatment system of claim 3 wherein: the handleand the at least one blade have at least one cooperating cam andfollower, the actuation of the handle causing the at least one cam andfollower to move relative to one another to move the at least one bladeinto and out of engagement with the at least one blade receivingopening. 5- The water treatment system of claim 3 wherein: the handleincludes at least one cam groove therein and the at least one bladeincludes at least one pin, the at least one pin moving within the atleast one cam groove as the handle is actuated to move the at least oneblade into and out of engagement with the at least one blade receivingopening. 6- The water treatment system of claim 5 wherein: the handle isgenerally U-shaped and includes a pair of spaced apart cam earsconnected by a bight portion, each of the cam ears including a camgroove therein; and the at least one blade includes a pair of pins, eachpin being disposed in a cam groove of the handle; wherein the handle maybe pivoted relative to the closure causing the pins to travel within thecam grooves and the at least one blade to reciprocate into and out ofengagement with the at least one blade receiving opening. 7- The watertreatment system of claim 6 wherein: the handle further comprises anaxle extending between the spaced apart cam ears; and the closureincludes at least one bearing formed thereon, the axle being rotatablysupported within the at least one bearing allowing the handle to pivotrelative to the closure. 8- The water treatment system of claim 7wherein: the closure includes an O-ring which sealingly mates with thehousing assembly when the closure is secured to the housing assembly. 9-The water treatment system of claim 1 wherein: the housing assemblyincludes a blade receiving opening and; the attachment mechanismincludes a handle and a pair of blades; the handle being pivotallyactuatable with respect to the closure to reciprocate the blades intoand out of engagement with the blade receiving opening. 10- Apoint-of-use water treatment system for home or office use, the watertreatment system comprising: a filter housing assembly having a filterchamber for receiving a filter and a circumferentially and continuouslyextending blade receiving opening; a closure which releasably seals withthe filter housing assembly to form a closed pressure vessel, theclosure including at least one bearing formed thereon and an O-ringwhich sealingly mates with the housing assembly when the closure issecured to the housing assembly; and an attachment mechanism having ahandle and a pair of blades to releasably secure the closure to thehousing, the handle being generally U-shaped and including a pair ofspaced apart cam ears connected by a bight portion and an axle extendingbetween the spaced apart cam ears, each of the cam ears including a pairof cam grooves and the blades each including a pair of pins, each pinbeing disposed in a cam groove of the cam ears; wherein the handle maybe pivoted with the axle rotating upon the bearing causing the pins tomove within the cam grooves and the blades to reciprocate into and outof engagement with the blade receiving opening. 11- A method of creatinga pressure vessel in a point-of-use water treatment system, the methodcomprising the steps of: placing a closure in sealing engagement with afilter housing assembly to effect a seal therebetween and forming apressure vessel, the filter housing having a filter therein forfiltering water flowing through the water treatment system; andactuating an attachment mechanism which uses a mechanical advantage toreleasably secure the closure to the housing assembly. 12- The method ofclaim 11 wherein the step of actuating an attachment mechanismcomprises: pivoting a handle relative to the closure to cause at leastone blade to reciprocate into releasable engagement with a bladereceiving opening in the housing assembly thereby releasably securingthe closure to the housing assembly. 13- A point-of-use water treatmentsystem for home or office use, the system comprising: a base; a filterhousing assembly mounted relative to the base; a filter disposed withinthe filter housing for filtering water passing through the filterhousing assembly; a UV tank assembly mounted relative to the base; a UVbulb assembly disposed within the tank assembly for irradiating waterpassing therethrough; and a heat dissipating support plate, having arelatively high thermal conductivity, which is mounted juxtaposed thetank assembly; and a housing generally enclosing the filter housingassembly and the tank assembly; whereby heat generated by the UV bulbassembly and transferred to the tank assembly is readily transferable tothe support plate and then the atmosphere. 14- A point-of-use watertreatment system for home or office use, the system comprising: a base;a UV tank assembly mounted to the base; an electrical connector capassembly mounted to the tank assembly, the cap assembly having a firstset of electrical contacts; a UV bulb assembly including a UV bulb and ahead assembly, the head assembly having a handle, a seal and a secondset of electrical contacts; wherein the handle may be used to releasablymount the UV bulb within the tank assembly with the seal sealing withone of the tank assembly and cap assembly to form a closed pressurevessel and the first and second sets of contacts engaging one another toplace the UV bulb assembly and cap assembly in electrical communication.